code: def set_epoch(self, epoch):
      super().set_epoch(epoch)
      for ds in self.defn.values():
          ds.set_epoch(epoch)
  
file_path: fairseq/fairseq/data/nested_dictionary_dataset.py
imports: from collections import OrderedDict
  import torch
  from torch.utils.data.dataloader import default_collate
  from .None import FairseqDataset
label_desc: Use image node_id 10 for calling the NestedDictionaryDataset obj's underlying member method code with example usage: obj.set_epoch(epoch) without return types